Assing a int * to int which retruns segmentation fault-CodePudding

#include <iostream>

int main() {
    // Write C   code here
    int *p = reinterpret_cast<int*>(50);
    int q = 0;
    q = *p;
    std::cout << q;

    return 0;
}

I want to assign a int * to the int. even if I am doing reinterpret casting to store in the int variable still showing segmentation fault. Please help me to fix this

CodePudding user response：

The problem is not the reinterpret_cast, the problem is this line:

q = *p;

You try here dereference a pointer with address 50 which is an invalid address. If you want to assign the value of the pointer itself, you need to get rid of dereferencing operator * and use one more reinterpret_cast to cast pointer back to int (or rather long int).

But I have to agree with comments above: either you are just exploring how reinterpret_cast works or you're probably doing something wrong (depends on what you want to achieve with this code).

CodePudding user response：

In the above code, I am assigning 50 as value to the pointer p but it is really store as a address of p. As @drescherjm said, I am trying to access invalid address in the next line. hence it is returning segmentation fault.

The actual answer to copy the int* to int is,

Blockquote

int s = 50; int *p = &s; int q = *p;